Printer control system

ABSTRACT

A printer utilizes a core storage print buffer for characters to be printed, and a read only storage device for document carriage or format control and type chain character reference. The carriage control and type chain character portions of the read only storage device, and the print buffer all have a common data register used for readout to print or operate the carriage.

United States Patent Washington 1 Mar. 21, 1972 [s41 PRINTER CONTROL SYSTEM 3,3o7,|53 2/1967 Bauer ..340/172.s

3,343,l3l 9/1967 Bloom, Jr. et al. [72] w'shinam' Resmn' 3,311,323 2/1968 Taub .340/113 [73] Assignee: International Business Machines Corpora- 3,408,633 10/1968 Shimabukuro l0l/93 X tion, Armonk, NY.

- Prima Examiner-Paul J. Henon 22 Fl d: Dec. 9,1969 l 1 I e Assistant Examiner-Paul R. Woods 1 pp 333,528 Attorney-Hanifin and Jancin and Francis V. Giolma 52 us. Cl ..340/172.s, 101/93 ABSTRACT [51] "Gllc 9/00 A printer utilizes a core storage print buffer for characters to 58 Field of Search ..340/|72.s, r73; 101/93 be primed. and Md only storage device for docunmt cab riage or format control and type chain character reference. [56] Rem-nus Cited The carriage control and type chain character portions of the UNITED STATES PATENTS read only storage device, and the print huffcr all have a common data register used for readout to print or operate the car- 3.248,708 4/[966 Haynes ..340/172.5 i 3,284,777 I l/l966 Carlstrom et al ...340/l72.5 3,292, l 52 l2/l966 Barton ..340/l 72.5 11 Claims, 32 Drawing Figures PUESE DRIVE OPERATION BLOCK OVERFLDW l6 REGlSTER COUNTER 68 COUNYER 7U EHITTER 32 g smiwfimmi none 5 R VALIDITY COMPARE 66 J STORE 34 w? @m'h C YDRIVEHS 2B 14 62 g roan/n D 0 A n a omvs 0 U 05 PRINT N P k r E Ts T 1H8 CARRIAGE DRIVE s f E i HAMMER uo-co E E n 6 mm CHECK R g 5 noun/mus mu um A mon COMPUTER R I2 X64 Wk RQS.

50 TIMING 1 DECODE L PRINT MEMORY CYCLE c ctocr COUNTER 58 um sum/m 52 Pssr PAIENIEuI-Mw 1912 3,651,487

SHEET 01UF28 $33 DRIVE OPERATION amen (JVERFLOW I6 REGISTER couum as COUNTER 1o EHITTER P c f i f s T 2% u EMITTER RESET mman DRIVERS STORE 34 i 26'J1 BRIE-Ac I YDRIVERS s2 s4 FORMAT D0 22 24 [20 A 3 SEARCH DRIVE DU/ 'x M I PRmT* f o E P r 55 f ,com: BUFFER U ma CARRIAGE DRWE v lsfi E- HAMMER uo-co g G MATRIX CHECK s g COMHANDSANDDATA; n E FROM COMPUTER i sonumc DECODE axams. 4

ADDRESS $258.5 mm CARRIAGE 44 T 142 ADVANCE DRWE LINES CHARACTER OFF LINE TEST+ COUNTER COUNTER E RESET omvz RESET TEST/Di sum FORMAT 46 HOME SEARCH 0R (1ST PS8) PS5 f BUFFERSWRE /5s PRINT scan isms? so CONTROLS CONTROLS l MC L L PRINT mom CYCLE mama CLOCK COUNTER 5a 1 DATA STR0BE-----J 52 Pss+- INVENTOR. RICHARD s. WASHINGTON ATTORNEY PATENTEOIIIARZT I972 3.651.487

sum 02M 28 TRTTRTER DTTA REC TO OPERATION REGISTER RESET STORE SE NT ADVANCE GATE BUFFER SET E55 STORE TER YES CA FTRRREE RESET MOTION PRINT GATE FIG. 2

PAIENTEnnARzl I972 3,551,4 7

SHEET 03 [IF 28 FG. 3a m 3H5 CE TEST OFF RATE LOAD z Um STORE mu OR cmcw L 570 STORE max emu STORE & 0P RESET STORE M1 (IF NOT um W5 5 N 5 L N 57b L a DP SET R j F 1 ,SIORE cm 5n 51 cum STORE ADD. DRV. RESET smie cm ,so we 6 0sc HT RESET H I 8 J 056 P..B1Hfi [5121 H 53d W N \w/ SCAN MEMORY: cYqLE pm: C 58 32 GATE 1: 2 l 4 :a :16 {"5 2 32 fi scmcfifi R L PRICATE y T5 58 PSSP- C PRT.s- 5 N 2 smm b 32 539 L R F PRINT GhTE 53 BUFF FULL g R m a. 114 +3 GATE E EXTPRT. Q co a ss cm 59 32 +scm cow SETTLE TIME 4 0R L SENLE PRINT cm an 1m 1 PATENTEDMARZI m2 3.651.487

SHEET Ch 0F 28 162 FIG. 3b

I620 I 1 SP 32e a AMP SS 52A q B 320 e HP 42F -11ST PSSP %AMP 38 5 R f, m m m 3 4st 1 48h 489 M a /I@ a WAN" SAMPLES 1 I m; 2 yum SAMPLE a PRINT ADD. DRV.

g \4 r5 L TjEQB \2 -fi/ i l 1 2 M on cm.

4 CTRDRV. on R E a RESET SIGNAL 53b 48C 55%" TIME SCAN GATE amps? U 1 HWIWE L fiwscm WRITE mea g a 486 gvm w d i wmm HI ;ww R swam RI R T smnm PW 48k nmmcm 1 a1 4 E a 1'6 16 352 32 PMENTEDMARZ] I972 sum UBUF 28 FIG. 3f

BUFFER ADDRESS MATRIX RD we 5 s a PAIENTEImaz: I872 3.651.487

SHEET IQUF 28 LINE cm ans; CARRIAGE no cm. FORMATSEARCHZ TST STORE CHARACTER CTR SCAN L T A TIME t 1 1 420 I j GATE i'AIENTEnmzr I972 3.651.487

sum 130F 2::

DATA REG. RES.

a? Md UNASSIGNED 7 R s R -1 9 a m I49 a S N \R\ F? 114v J N F 1 R r PMENTEUMRZI m2 3.651.487

sum 16 or 28 MANUAL 0P 1 0P RESET,

OR m mama;-

' SKIP OPSUF 16 OPERATION REG STOP "5 SAMPLE;- B004 16d DATAREL'T '6 50P2R46-2 a 2 l 3 6h fld um E OR Ric? L f 1 9 J2 N FFJ He H 0Pi -1B-1 &

15 Hg fin 16b \e-a m. n

BEDS a 5 N a DATA s 0P 8 a REGS R F j a m We 16h lSm BCDA -a. 0R {CARR DATA j START a REES RESTORE nk Hp SET 16 L a 0R 5 N k m 0m 0P REG? 7 sup/ a OR SPACE am TEST STORE} FIG. 3n

TATENTEOHARZT I972 3.651.487

' sum 18 or 28 RESTORE SET RESET SIGNAL 5Q UNES COUNTER CARRIAGE CONTROL 1 CARRIAGE CONTROL 2 L TEST FIG. 3p 

1. In a control system for a printer having a type character bearing element movable to present different type characters at a plurality of print positions, a plurality of print hammers having control means operable to effect impact between selected ones of said type characters and a document on which a printing operating is to be performed, and a carriage having drive means controlled by carriage drive control means to advance said document for printing thereon at different line positions, a first storage means having a plurality of storage positions storing coded representations of characters to be printed on said document and having readout means for in turn reading out said coded representations to be printed at each of a plurality of positions on said document, a second storage means having a plurality of storage positions storing coded representations of type characters on said type character bearing element and having readout means for in turn reading out said type character coded representations for said type characters on said type character bearing element located instantaneously at each of said plurality of positions on said document, a single multi-bit register, circuit means connecting both of said storage means sequentially to said multi-bit register to control the condition of said multi-bit register in accordance with said readouts of said representations of a character to be printed and a character on said character bearing element located at one of said print positions, and additional circuit means connecting said multi-bit register to said print hammer control means to effect a selective operation of said print hammers in accordance with a predetermined condition of said register after said readouts.
 2. The invention as defined in claim 1 characterized by one of said storage means comprising a magnetic core storage device storing a binary coded representation of each of said characters to be printed and the other of said storage means comprising a read only capacitor storage device having a readout which is the complement of the binary coded representation of the characters on said character bearing element, said circuit means causing the readout from both of said storage means to be sequentially entered into said multi-bit register in a bit-by-bit parallel binary addition operation without carry such that the contents of said multi-bit register are all one bits if and only if the character representation read from one of said storage means is identical to the character representation read in complement form from the other of said storage, and said additional circuit means including compare means comprising an AND circuit having an output connected to said print hammer control means and having a plurality of inputs with one of said plurality of inputs being connected to each position of said multiposition register.
 3. The invention as defined in claim 2 characterized by said circuit means including also means connected to said second storage means readout means to provide a second readout of the type character coded representations to reconstruct in said single multi-bit register a coded representation readout of said first storage means into said single multi-bit register.
 4. The invention as defined in claim 2 characterized by said read only storage device having more bit positions per stOrage position than said multi-bit register, and circuit means connecting said read only storage device bit positions to said register in two separate groups.
 5. The invention as defined in claim 4 characterized by a line counter connected to said read only storage device to address said read only storage device and circuit means connected to said read only storage device to enable readout of one group of bit positions and inhibit said other group of bit positions.
 6. The invention as defined in claim 5 characterized by the read only storage device having two groups of bit positions representing carriage control signals in each of a limited number of storage positions which number is less than the maximum number of lines for a document, said line counter having sufficient stages to provide a count of double said limited number of storage positions in each group of bit positions of the read only storage device, and means including a plurality of gate devices connected to said data register and to different stages of said line counter to gate bits from one of said two groups of read only storage device bit positions during the first half portion of the lines counter count, and from the other of said two groups during the second half of the lines counter count.
 7. The invention as defined in claim 2 characterized by an address counter connected to clock means for addressing the different storage positions of said magnetic core storage device.
 8. The invention as defined in claim 7 further characterized by format search circuit means connected to said read only storage means to address said one group of bit positions containing representations of a carriage control signal and connected to said address counter for operating said address counter to count said carriage control signals in said read only storage means.
 9. The invention as defined in claim 8 characterized by circuit means connecting said line counter to said format search circuit means, a check trigger connected to said carriage control means and compare means connected to said line counter and said check trigger for checking carriage operations.
 10. The invention as defined in claim 9 characterized by circuit means connecting said read only storage means to said magnetic core storage means through said multi-bit register for loading said magnetic core storage means from said read only storage means, and means connected to said lines counter to force a single space carriage operation and advance the lines counter one count whereby each subsequent loading of the magnetic core storage means from said read only storage means is advanced one address position to cause said printer to print a diagonal print test pattern from representations in said read only storage means.
 11. The invention as defined in claim 9 characterized by said read only storage device containing 1, NOT 2 heading line codes in one or more storage positions, and an operation counter connected to be responsive to a predetermined channel number skip command, a block counter connected to said multi-bit register of the read only storage device to be advanced by each readout of carriage control 1, NOT 2 heading line codes stored in said storage device, and compare means connected to said operation counter and said block counter for stopping said line counter when the count of said block counter equals the count of said operation counter. 